With the wide spread of high-definition video, the specialization of video application renders higher demands for encoding. In the field of monitoring, the resolution of the video is higher and higher, and the compression rate of the video is strictly required based on the requirements of transmission bandwidth and storage, so that the improvement of the encoding quality and the compression rate of the monitored video becomes an explicit requirement. For video encoding processing, the higher the image frame rate, the higher the encoding rate is required. How to flexibly change the encoding image frame rate according to the characteristics of video image data and transmission bandwidth can effectively control the video encoding rate.
In video monitoring applications, for encoded scenes, the background is always mostly stationary while the foreground object is moving, but the foreground moving object is the area of interest. Therefore, with the characteristic of static monitoring scene background being effectively utilized, the encoding rate of the non-interested area being reduced, the video encoding compression rate can be greatly improved. In addition, in the existing variable frame rate implementation scheme, the frame rate change of the encoded frame is generally controlled from the angle of rate control, and there is no method for changing the frame rate from the angle of macro block encoding based on image content.